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961.
Sekineh Bakhshandeh Rostami Ehsan Saljoughi Seyed Mahmoud Mousavi Shirin Kiani 《先进技术聚合物》2022,33(1):340-352
Polyphenylsulfone (PPSU) was applied for the first time in the hydrophobic PV process. Nanocomposite membranes of PPSU/graphene (Gr) nanosheets were prepared and used to separate isopropyl benzene (cumene) from water via pervaporation (PV). Analysis of the mechanical properties of the membranes showed that the tensile strength and Young's modulus had an increasing trend with the incorporation of Gr into PPSU. The water contact angle of the membranes had a rising trend with the addition of Gr, confirming the improved hydrophobicity of membranes. In the PV experiments, the membrane containing 3.5 wt% Gr provided the highest separation factor, which was 4.5-fold as much as that of the neat PPSU membrane. Cumene separation from water by the PPSU/3.5 wt% Gr membrane was associated with the total flux of 132.73 gMH, the separation factor of 1566.36, and the PSI of 208,124.8 gMH. 相似文献
962.
Naeem Nida Khoja Asif Hussain Butt Faaz Ahmed Arfan Muhammad Liaquat Rabia Hasnat Amin Ul 《Research on Chemical Intermediates》2022,48(5):2007-2034
Research on Chemical Intermediates - In this study, biomass fly ash (BFA)-supported Ni/CaO catalyst was synthesized, characterized and evaluated for partial oxidation of methane (POM) in a fixed... 相似文献
963.
Amiri Delouei Amin Emamian Amin Karimnejad Sajjad Sajjadi Hasan Jing Dengwei 《Journal of Thermal Analysis and Calorimetry》2021,144(3):611-621
Journal of Thermal Analysis and Calorimetry - This study aimed at presenting a steady-state analytical solution for the two-dimensional heat conduction in a cylindrical segment made of functionally... 相似文献
964.
Pourfattah Farzad Sabzpooshani Majid Toghraie Davood Asadi Amin 《Journal of Thermal Analysis and Calorimetry》2021,144(1):189-201
Journal of Thermal Analysis and Calorimetry - Heat transfer and fluid flow are optimized in a three-dimensional channel under the constant heat flux boundary condition employing a genetic algorithm... 相似文献
965.
Alexandra Quek Nur Kartinee Kassim Amin Ismail Muhammad Alif Mohammad Latif Khozirah Shaari Dai Chuan Tan Pei Cee Lim 《Molecules (Basel, Switzerland)》2021,26(1)
The present study investigated the antidiabetic properties of the extracts and fractions from leaves and stem bark of M. glabra based on dipeptidyl peptidase-4 (DPP-4) and α-Amylase inhibitory activity assays. The chloroform extract of the leaves was found to be most active towards inhibition of DPP-4 and α-Amylase with IC50 of 169.40 μg/mL and 303.64 μg/mL, respectively. Bioassay-guided fractionation of the leaves’ chloroform extract revealed fraction 4 (CF4) as the most active fraction (DPP-4 IC50: 128.35 μg/mL; α-Amylase IC50: 170.19 μg/mL). LC-MS/MS investigation of CF4 led to the identification of trans-decursidinol (1), swermirin (2), methyl 3,4,5-trimethoxycinnamate (3), renifolin (4), 4′,5,6,7-tetramethoxy-flavone (5), isorhamnetin (6), quercetagetin-3,4′-dimethyl ether (7), 5,3′,4′-trihydroxy-6,7-dimethoxy-flavone (8), and 2-methoxy-5-acetoxy-fruranogermacr-1(10)-en-6-one (9) as the major components. The computational study suggested that (8) and (7) were the most potent DPP-4 and α-Amylase inhibitors based on their lower binding affinities and extensive interactions with critical amino acid residues of the respective enzymes. The binding affinity of (8) with DPP-4 (−8.1 kcal/mol) was comparable to that of sitagliptin (−8.6 kcal/mol) while the binding affinity of (7) with α-Amylase (−8.6 kcal/mol) was better than acarbose (−6.9 kcal/mol). These findings highlight the phytochemical profile and potential antidiabetic compounds from M. glabra that may work as an alternative treatment for diabetes. 相似文献
966.
The pH-metric studies on the interaction of divalent metal cations, Co (II), Ni (II) and Cu (II) with lomatiol have been performed under the thermodynamic conditions achievable at constant ionic strength and infinite dilution in which a mole of divalent metal, combined with 02 mol of lomatiol. Lomatiol being bidentate could replace two water molecules at a time. The values of stepwise formation constants showed no conspicuous difference at 25 °C and 35 °C, and the complexes, registered a decrease in their stability values suggesting the low temperature as a favorable condition under which the chelation of metal with lomatiol is feasible. The reaction takes place without the use of any specific catalyst although under alkaline conditions. The reactions of lomatiol with metal cations in solution had been adjudged as the spontaneous reaction on account of the negative ΔG value in all the metal lomatiol systems. Also the study showed the positive experimental values of entropy changes in all the systems and negative value of free energy. The continuous fall in the values of the stepwise formation constants (k1 > k2 > k3) in the divalent metal-lomatiol system has been assigned to the statistical factor. 相似文献
967.
Dr. Abdolhossein Miri Dr. Hakimeh Najafzadeh Dr. Majid Darroudi Dr. Mohammad Javad Miri Dr. Mohammad Amin Jadidi Kouhbanani Mina Sarani 《ChemistryOpen》2021,10(3):327-333
Iron oxide nanoparticles have attracted much attention because of their superparamagnetic properties and their potential applications in many fields such as magnetic storage devices, catalysis, sensors, superparamagnetic relaxometry (SPMR), and high-sensitivity biomolecule magnetic resonance imaging (MRI) for medical diagnosis and therapeutics. In this study, iron oxide nanoparticles (Fe2O3 NPs) have been synthesized using a taranjabin (camelthorn or persian manna) aqueous solution. The synthesized Fe2O3 NPs were identified through powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), field energy scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX), vibrating-sample magnetometer (VSM) and Raman technics. The results show that the nanoparticles have a hexagonal structure with 20 to 60 nm in size. The cytotoxic effect of the synthesized nanoparticles has been tested upon application against lung cancer cell (A549) lines. It was found that there is no cytotoxic activity at lower concentrations of 200 μg/mL. The ability of the synthesized nanoparticles for lead removal in wastewaters was tested. Results show that highest concentration of adsorbent (50 mg/L) has maximum removal efficiency (96.73 %). So, synthesized Fe2O3 NPs can be a good candidate to use as heavy metals cleaner from contaminated waters. 相似文献
968.
We report on lithium ion conductivity and diffusivity along major crystallographic directions of Al-doped LiFePO4 single crystals. Impedance spectroscopy as well as galvanostatic polarization measurements have been carried out on the electronically blocking symmetric cell LiAl/LiI/LiFe(Al)PO4/LiI/LiAl. Neither ionic conductivity nor lithium diffusivity show anisotropy in the bc planes within the experimental error, but much lower values in the a-direction. Similar features were observed earlier by us for the pure single-crystal and the Si-doped single crystal. On Al-doping the ionic conductivity has increased while the electronic conductivity has decreased compared to undoped LiFePO4. Not only this donor doping effect but also the temperature dependence of ionic conductivity and of lithium-diffusivity are successfully interpreted in terms of lithium vacancies, holes and associates in the framework of a detailed defect chemical analysis. Ion-electron as well as ion-ion associates play a significant role in this system. 相似文献
969.
The reaction of diarylacetylenes with CoCl(PPh3)3 and sodium cyclopentadienylide or sodium carbomethoxycyclopentadienylide gave (η4-tetra-arylcyclobutadiene)(η5-cyclopentadienyl)cobalt and (η4-tetra-arylcyclobutadiene)(η5-carbomethoxycyclopentadienyl)cobalt, respectively, where aryl = para-XC6H4 (X = CF3, F, MeO). The reaction was unsuccessful for the synthesis of (η4-tetra(para-methoxyphenyl)cyclobutadiene)(η5-cyclopentadienyl)cobalt, which was synthesised instead from dicarbonyl(η5-cyclopentadienyl)cobalt. In all of the examples starting with CoCl(PPh3)3 an intermediate (η5-cyclopentadienyl)- or (η5-carbomethoxycyclopentadienyl)(triphenylphosphine)-2,3,4,5-tetraarylcobaltacyclopentadiene complex was isolated, and two examples were characterised by X-ray crystallography. Heating the (η5-cyclopentadienyl)- or (η5-carbomethoxycyclopentadienyl)(triphenylphosphine)-2,3,4,5-tetraarylcobaltacyclopentadiene complexes resulted in clean conversion to the corresponding metallocenes. The influence of the para-aryl substituents on the 1H NMR of the cyclopentadienyl moiety is tabulated, together with the influence of a range of R substituents in (η4-tetraphenylcyclobutadiene)(η5-RC5H4)cobalt (R = CO2Me, CH2OH, Me, CHO, CCH, CO2H, CN, CONHR1, 2-oxazolinyl, NH2, NHAc, HgCl, Br, I, SiMe3, SnMe3, Ph). 相似文献
970.
Dr. Sharad S. Amin Dr. Kieran D. Jones Dr. Alexander J. Kibler Dr. Heather A. Damian Dr. Jamie M. Cameron Dr. Kevin S. Butler Dr. Stephen P. Argent Max Winslow Dr. David Robinson Dr. Nicholas J. Mitchell Prof. Hon Wai Lam Dr. Graham N. Newton 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302446
Herein, we report the synthesis and characterization of a new class of hybrid Wells–Dawson polyoxometalate (POM) containing a diphosphoryl group (P2O6X) of the general formula [P2W17O57(P2O6X)]6− (X=O, NH, or CR1R2). Modifying the bridging unit X was found to impact the redox potentials of the POM. The ease with which a range of α-functionalized diphosphonic acids (X=CR1R2) can be prepared provides possibilities to access diverse functionalized hybrid POMs. Compared to existing phosphonate hybrid Wells–Dawson POMs, diphosphoryl-substituted POMs offer a wider tunable redox window and enhanced hydrolytic stability. This study provides a basis for the rational design and synthesis of next-generation hybrid Wells–Dawson POMs. 相似文献